Did you see a huge military plane in flight? Here's what's up

Large military transport planes will be landing and taking off at Harrisburg International Airport through Monday, according to a news release.

The planes will take part in an emergency-preparedness exercise, known as the Vigilant Guard, held by the Pennsylvania National Guard. The C-5s and C-17s are among the largest military aircraft in the world, the release states.

The Vigilant Guard is a quarterly exercise to improve cooperation and effectiveness between National Guard units and state and federal first responders in preparation for emergencies and catastrophic events, the release states.

"It's not every day we get a chance to see these large cargo planes in our area," Capt. Jay Ostrich, spokesperson for the 193rd Special Operations Wing, which will host the aircraft, said in the release. "If you see an increase in military aircraft overhead, don't worry, it's all a part of a controlled and carefully planned exercise."